Replaceable detection module

ABSTRACT

We describe a detection module useful with an apparatus and/or system for conducting luminescence assays, and a kit, a system, an apparatus, and a method incorporating the detection module.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.12/932,836, filed Mar. 8, 2011, allowed; which claims the benefit ofU.S. Provisional Application Nos. 61/339,790 and 61/339,789, each filedon Mar. 9, 2010, each disclosure of which is incorporated herein byreference in its entirety; this application is related to U.S.Provisional Application No. 61/123,975, filed Apr. 11, 2008; U.S.Provisional Application No. 60/752,475, filed Dec. 21, 2005; U.S.Provisional Application No. 60/726,023, filed Oct. 11, 2005; U.S.Provisional Application No. 60/752,513, filed Dec. 21, 2005; U.S.application Ser. No. 11/642,970, filed Dec. 21, 2006; U.S. applicationSer. No. 11/642,968, filed Dec. 21, 2006; and U.S. application Ser. No.12/422,081, filed Apr. 10, 2009, the disclosures of each of theseapplications are incorporated herein by reference in their entireties.

FIELD OF THE INVENTION

The invention relates to a detection module used in an apparatus and/orsystem for conducting assays. Certain embodiments of the apparatusand/or system may be used for conducting automated sampling, samplepreparation, and/or sample analysis in a multi-well plate assay format.

BACKGROUND OF THE INVENTION

Numerous methods and systems have been developed for conductingchemical, biochemical, and/or biological assays. These methods andsystems are essential in a variety of applications including medicaldiagnostics, food and beverage testing, environmental monitoring,manufacturing quality control, drug discovery, and basic scientificresearch.

A variety of plate readers are available for conducting assaymeasurements in multi-well plates including readers that measure changesin optical absorbance, emission of luminescence (e.g., fluorescence,phosphorescence, chemiluminescence, and electrochemiluminescence),emission of radiation, changes in light scattering, and changes in amagnetic field. U.S. Patent Application Publications 2004/0022677 and2005/0052646 of U.S. patent application Ser. Nos. 10/185,274 and10/185,363, respectively, of Wohlstadter et al. describe solutions thatare useful for carrying out singleplex and multiplex ECL assays in amulti-well plate format. They include plates that comprise a plate topwith through-holes that form the walls of the wells and a plate bottomthat is sealed against the plate top to form the bottom of the wells.The plate bottom has patterned conductive layers that provide the wellswith electrode surfaces that act as both solid phase supports forbinding reactions as well as electrodes for inducingelectrochemiluminescence (ECL). The conductive layers may also includeelectrical contacts for applying electrical energy to the electrodesurfaces.

Prior plate readers, including those capable of forming an image ofluminescence generated in the plate wells, contain a detection mechanismthat is an inseparable, integrated part of the plate reading apparatus.Repair of a component of the detection mechanism is, therefore, carriedout in a piecemeal manner. In addition, a design or engineering changeto one or more components of the apparatus that could functionindependently of the detection mechanism, such as a plate stacker, mightrequire a consequent re-design of detection mechanism componentsphysically associated with or otherwise impacted by such a changedapparatus component. Such alterations might lead to inconsistentperformance within or across product lines despite their using the samebasic detection components. Yet, detection systems serve a core functionto all luminescence based readers, in contrast to those mechanisms thatserve to receive the samples and deliver them into the system in any oneof a number of formats (e.g., plates, cartridges, flow cells).Therefore, there is a need for a core detection module that can bemanufactured, serviced, replaced, and integrated interchangeably into avariety of reading apparatuses as a self-contained sub-assembly.

SUMMARY OF THE INVENTION

The invention provides a detection module for use with an apparatus forconducting luminescence assays, the apparatus comprising one or moredetection module engagement elements, the detection module comprising ahousing with the following components disposed within the housing: (a) alight detector; and (b) a control board comprising (i) amicrocontroller; (ii) motion control and communications electronics;(iii) an external input/output connector; and (iv) an internalinput/output connector, wherein the housing comprises one or moreapparatus engagement elements configured to align and engage with theone or more detection module engagement elements. In a preferredembodiment, the apparatus is configured to conduct a luminescence assayusing a multi-well assay plate.

Also provided is a system comprising (a) an apparatus for conductingluminescence assays in multi-well plates, the apparatus comprising alight-tight enclosure (LTE), a fluidic assembly, an imaging assembly, aplate assembly capable of supporting and translating a plate to one ormore components of said apparatus; and one or more detection moduleengagement elements; (b) a detection module for use with the apparatus,the detection module comprising a housing with the following componentsdisposed within the housing: (x) a light detector; and (y) a controlboard comprising (i) a microcontroller; (ii) motion control andcommunications electronics; (iii) an external input/output connector;and (iv) an internal input/output connector, wherein the housingcomprises one or more apparatus engagement elements configured to alignand engage with the one or more detection module engagement elements.

Still further, the invention contemplates a method of conducting aluminescence assay in an assay system as described herein comprising:(a) inserting the detection module into the apparatus; (b) engaging theapparatus and detection module engagement elements; (c) inserting themulti-well assay plate within a light-tight enclosure of the apparatus;(d) generating a current/voltage waveform in the detection module; (e)providing electrical energy to a well of the assay plate in thelight-tight enclosure; and (f) measuring luminescence from the assayplate in the detection module.

The invention also provides an apparatus for conducting luminescenceassays in multi-well plates, the apparatus comprising a light-tightenclosure (LTE), a fluidic assembly, an imaging assembly, a plateassembly capable of supporting and translating a plate to one or morecomponents of the apparatus; and one or more detection module engagementelements configured to align and engage with a detection module via oneor more apparatus engagement elements position on the detection module.

The invention further provides a kit comprising a detection module asdescribed herein and a device comprising software to (i) operate saiddetection module and/or said apparatus, and/or (ii) manage and/oranalyze data collected on said apparatus and/or detection module.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1A shows a view of one embodiment of an assay system of theinvention, including a detection module aligned and engaged with anapparatus.

FIGS. 1B-1C provide an isometric view of one embodiment of the assaysystem and a corresponding side view, respectively.

FIG. 2 shows a top view of an assay system of the invention.

FIGS. 3A-3B is a view of the detection module of the invention with thehousing (FIG. 3A) and the various components of imaging system withinthe housing (FIG. 3B).

DESCRIPTION OF SPECIFIC EMBODIMENTS OF THE INVENTION

The Detailed Description section provides descriptions of certainembodiments of the invention that should not be considered limiting butare intended to illustrate certain inventive aspects. Unless otherwisedefined herein, scientific and technical terms used in connection withthe present invention shall have the meanings that are commonlyunderstood by those of ordinary skill in the art. Further, unlessotherwise required by context, singular terms shall include pluralitiesand plural terms shall include the singular. The articles “a” and “an”are used herein to refer to one or to more than one (i.e., to at leastone) of the grammatical object of the article. By way of example, “anelement” means one element or more than one element.

Described herein is a detection module used with an apparatus forconducting luminescence assays. As used herein, an assay system refersto the apparatus including an integrated detection module, i.e., adetection module that is mounted to and properly aligned with anapparatus. The detection module is a single, self-contained, replaceableunit within a housing comprising various components used with anapparatus, e.g., a camera and lens, a main control printed circuit boardincluding an optional computer module, and associated mechanicalstructural components and cabling. The components within the detectionmodule interface with the apparatus upon proper alignment and engagementof the detection module to enable the conduct of an assay with theapparatus/assay system. A detection module of the present inventionprovides standardized manufacturing and performance characteristicsacross a range of apparatus formats into which it may be integrated.

The detection module includes one or more alignment and engagementelements that mate to one or more apparatus alignment and engagementelements, to support and ensure the proper alignment of the detectionmodule within the apparatus. These elements can include engagementelements such as tabs, slots, pins, guide holes, latches, lockingmechanisms, and the like. In the detection module, the one or morealignment and engagement elements are referred to as “apparatusengagement elements” because they facilitate proper alignment andengagement of the detection module with the apparatus. Likewise, the oneor more alignment and engagement elements of the apparatus are referredto as “detection module engagement elements.” In one embodiment, thedetection module comprises a vertical tab and the apparatus comprises anengagement pin. When the detection module is inserted into theapparatus, the vertical tab of the detection module contacts theengagement pin, causing the detection module to lock into properorientation within the apparatus. The apparatus may also include a guidesurface adapted to receive and guide the detection module into positionwithin the apparatus. Alternatively, the apparatus may include a lockingmechanism comprising a spring loaded latch and a first pin configured toengage with the detection module and a second pin configured to engagewith a notch on the detection module, wherein movement of the detectionmodule into the apparatus contacts the first pin causing the latch torotate and the second pin to engage with the notch. The spring loadedrotating latch may include a spring to resist the rotation of the latch,and optionally, the resistance of the spring is reduced as the secondpin engages with the notch. The latch may also include a tab and thelocking mechanism further comprises an optical sensor, wherein the tabis configured to cover the optical sensor when the locking mechanism isengaged. The tab may include a pin extending down toward the opticalsensor.

FIG. 1A shows a view of one embodiment of an assay system of theinvention surrounded by system. FIG. 1A shows the relative position ofthe light-tight enclosure 120, input and output plate stackers, 121 and122, respectively, which are adapted to hold multi-well assay plates foruse in assays conducted in the system, and window 125, which provides anoptical path for a bar code reader (not shown) in the fluidic subsystemwithin the apparatus (not shown) to read bar codes on plates in inputstacker 121.

FIG. 1B provides an isometric view of one embodiment of the assay systemwith system housing 100 removed and incorporating detection module 130,aligned and engaged with apparatus 110 (which includes elements 120,121, 122, 123, 125, 135, and 140). Sliding light-tight door 140 providesa light-tight seal to plate introduction apertures (not shown) in thetop of light-tight enclosure 120 located under plate stackers 121 and122. Plate stackers 121 and 122 have plate release latches 123 that arespring loaded to allow plates raised from the light-tight enclosurebelow (using a plate elevator that is not shown in this view) to becaptured in the stack. The latches in the input stack can also bedirected to be released to allow plates to be released from the stack toa plate elevator below (not shown). A side view of the apparatus isshown in FIG. 1C, in which detection module, 130, is aligned withapparatus 110 and positioned on top of light-tight enclosure of theapparatus, 120, adjacent to a fluidic subsystem of the apparatus (notshown in this view), which is surrounded by support bracket 150 (also acomponent of the apparatus).

FIG. 2 shows a top view of the apparatus, including detection module 130aligned with the apparatus, including input and output plate stackers,121 and 122, and plate translation stage, 210. Fluidic subsystem (220)is used to deliver sample to the apparatus, wash the integrated pipettor(not shown), and dispose of waste from the pipettor (not shown). Motor230 is coupled via a belt to a linear screw drive (not shown) that opensdoor 140. Pipetting probe translation stage 160 provides horizontal andvertical translation of dual pipetting probe (not shown) and a piercingtool (not shown) is used to pierce and displace seals on wells of sealedplates so as to allow for unblocked imaging of the wells.

The module may include alignment mechanisms for adjusting the alignmentof internal module components after the module has been attached to anapparatus. FIG. 3A is a view of the detection module with a detectionmodule housing (310), including alignment mechanisms for X, Y, andZ-adjustment (320, 330 and 340, respectively) of the camera and lenswithin the detection module. In the specific embodiment shown in thefigure, set screws are used to align in the X and Y directions and adrive screw is used to focus the optical system in the Z direction. Awide range of alternative alignment mechanisms will be known to one ofaverage skill in the art. The alignment mechanisms can be configured tobe adjusted manually or, alternatively, can be motorized to enableautomated alignment.

FIG. 3B shows the various components of imaging system 350 within thehousing of the detection module. The imaging system includes a camera351 mounted on the top of light-tight enclosure (not shown) via camerabracket 352. Lens 353, coupled to camera 351, is used to provide afocused image of luminescence generated from plates in the light-tightenclosure. Diaphragm 354 sealed to lens 353 and an aperture in the topof the light-tight enclosure, allows imaging system 350 to image lightfrom the light-tight enclosure while maintaining the enclosure in alight-tight environment protected from environmental light. The maincontrol board 355 is also positioned within the detection module andincludes a microcontroller, motion control and communicationelectronics, a computer module, external and internal input/outputconnectors (not specifically shown).

In one embodiment, the invention provides a detection module comprisinga housing with the following components disposed within the housing: (a)a light detector; and (b) a control board comprising (i) amicrocontroller; (ii) motion control and communications electronics;(iii) optionally, a computer module; (iv) an external input/outputconnector; and (v) an internal input/output connector. As discussedabove, the detection module housing element is configured for placementwithin the apparatus. Providing a single, self-contained, replaceabledetection module that may be used with an apparatus in an assay systemprovides a number of significant benefits, including but not limited to,efficiencies in the manufacturing process and simplified maintenance andservice of the assay system and its component parts. Moreover, asdiscussed in more detail below, because various different detectionmodules may be used with a single apparatus, the present inventionprovides enhanced flexibility to the user that requires a range ofresults that may not be achieved with a single fully integrated system.

The detection module is configured to interface with the variouscomponents of the apparatus to control the mechanical and/or electronicsubsystems of the apparatus, analyzing the acquired data and/ordelivering analyzed data to a component of the apparatus, e.g., a userand/or system interface. In one embodiment, the microcontroller of thedetection module comprises firmware that interfaces with the softwarerunning on the apparatus. The firmware provides an interface thatsupports one or more of the following detection module functions: analoginput, digital input, digital output, PCB interrupt status, steppermotor control, and ECL waveform generation and electrode impedancemeasurements. In addition, the firmware enables board identification,operating status, and firmware revision management within the detectionmodule.

The detection module light detector may be a conventional light detectorsuch as a photodiode, avalanche photodiode, photomultiplier tube, or thelike. Suitable light detectors also include arrays of a plurality oflight detectors. Light detectors that may be used also include imagingsystems such as CCD and CMOS cameras. The light detector also includesoptics which collect light emitted from a multi-well assay plate andfocus that light on the light detector. Optics may also include, e.g.,elements that transmit, scatter, block, filter, modify, diffract,refract, and/or reflect light. Optics may include physical/mechanicalelements that provide structural support or couple the optical elementsto other elements of the apparatus. Examples of optics include but arenot limited to lenses, prisms, filters, splitters, mirrors, opticalfibers, optical couplers, optical epoxies and adhesives, windows,modulators, optical coatings and the like. The lens may be a highnumerical aperture lens which may be made from glass or injection-moldedplastic. CCD or CMOS cameras used in the module may be uncooled or maybe cooled to, e.g., 0° C., −10° C., −20° C., −40° C. or lower dependingon sensitivity requirements. In addition, optics may include filtersdesigned to selectively pass the luminescence generated from transitionmetal labels, particularly ruthenium-tris-bipyridine labels. In aspecific embodiment, the optics include a lens and a filter fordirecting, focusing and/or imaging light on the detector. The lightdetector may also incorporate control electronics, software, firmware,connectors, and high speed cables for efficient transfer of images tothe electronics and computer within the apparatus and/or the detectionmodule.

In one specific embodiment, the light detector comprises a lens, anoptical filter and a photodetector, e.g., a CCD camera. In oneembodiment, the light detector comprises a CCD camera comprisingfirmware. In addition, the light detector may include a diaphragm sealedto the lens and a detection module aperture in vertical alignment with alight-tight enclosure aperture to allow the light detector to imagelight from the light-tight enclosure while maintaining the light-tightenclosure in a light-tight environment protected from ambient light. Inone specific embodiment, the components of the light detector, e.g., thephotodetector comprising an imaging element, coupled to a lens, a filterelement and a diaphragm, are positioned above the detection moduleaperture and in vertical alignment with the light-tight enclosureaperture. In certain embodiments, an imaging element is used to imageluminescence from arrays of binding domains in one or more wells of anassay plate and/or one or more regions of an assay cartridge positionedwithin the apparatus and the assay apparatus reports luminescence valuesfor luminescence emitted from individual elements of the arrays.

Optionally, the detection module may further include a mechanism, e.g.,a wheel, ring or a through-hole into which a tool may be inserted foradjustment, located on the outside of the detection module housing, thatmay be used to manually control the movement of the light detector alonga vertical axis within the housing to control the focusing of the lightdetector within the detection module. In one embodiment, the detectionmodule may attach to a mount in the apparatus that comprises a manual orautomated axis of motion for moving the detection module up and down.Optionally, the detection module may remain static once placed withinthe apparatus, but the light detector components may move within thedetection module, controlled by an axis external to the module housing.Still further, the light detector components may move independently fromthe PCB located within the detection module. Alternatively, focus may becontrolled by one or more printed circuit boards and associated firmwarewithin the detection module housing.

In a specific embodiment, the imaging system within the detection moduleis capable of automatic X, Y and/or Z-training on an object within thelight-tight enclosure once the detection module is positioned within thechassis of the apparatus. For example, in order to insure properalignment of the optical components within the apparatus, the imagingsystem is programmed to focus on a pre-defined component or targetpositioned within the light-tight enclosure, e.g., on the platecarriage, a test plate, cartridge, etc. and image that target to adjustand confirm proper alignment of the imaging system to the light-tightenclosure. The firmware is programmed to align the detection module, theimaging system and/or one or more components within the light-tightenclosure in response to the output of the X, Y, and/or Z-training testto confirm proper alignment of the detection module and light-tightenclosure.

An assay system and apparatus may accommodate more than one type ofdetection module and the components within a detection module may differfrom those of another depending on the type of measurement required. Oneor more of the components of the detection module may vary, e.g., thetype or sensitivity of the light detector, dynamic range of the camera,and/or one or more elements of the control board. In one embodiment, afirst detection module may include a light detector that comprises a CCDcamera and a second detection module may include a photodiode.Alternatively, a first detection module may include a single lightdetector and a second detection module may include an array of lightdetectors. The following elements/components/characteristics may also bevaried in the construction of a detection module: lens design, lightguide configuration, sensitivity, dynamic range detection limits, and/ortemperature control, etc., and these detection module variations maylead to adjustments by the apparatus to conduct a measurement using agiven detection module, e.g., the characteristics of the waveformapplied by the apparatus. In one embodiment, a first detection modulemay include a high-resolution lens/CCD chip to yield a high-resolutiondetection module, and a second detection module may include alow-resolution lens/CCD chip to yield a low-resolution detection module.Alternatively, the detection module may include a plurality of CCD chipsto increase the throughput of the detection module.

Still further, the apparatus may include a series of detection modules,i.e., two or more detection modules, e.g., high- and/or low-resolutionmodules, on a platform positioned above the light-tight enclosure. Thetwo or more detection modules may be the same or different. In oneembodiment, a first detection module may be a high-resolution module andthe second detection module may be a low-resolution module. The use oftwo or more detection modules in an assay system increases thethroughput of the system because it enables simultaneous imaging of asingle multi-well plate. In this embodiment, the light-tight enclosureincludes two or more apertures that may be vertically aligned with twoor more detection module apertures. This configuration enables thesimultaneous analysis of two or more wells of a multi-well plate, suchthat a first detection module and a corresponding light-tight enclosureaperture is positioned above a first well or grouping of wells in amulti-well plate and a second detection module and a correspondinglight-tight enclosure aperture is positioned above a second well orgrouping of wells in the multi-well plate. In a preferred embodiment,the first detection module is aligned with a corresponding light-tightenclosure aperture which is positioned above a first half of amulti-well plate and a second detection module is aligned with acorresponding light-tight enclosure aperture which is positioned above asecond half of the multi-well plate.

During a measurement, a multi-well assay plate is placed within thelight-tight enclosure and positioned underneath the light-tightenclosure aperture and in vertical alignment with the detection moduleaperture. The light detector collects an image of a well or group ofwells of the multi-well plate and focuses that image onto the imagingelement of the light detector. The light detector acquires and,preferably, stores a background image to the control board and sendsdata to a computer within or attached to the apparatus via one or moreinternal and/or external I/O connectors. The apparatus makes electricalcontact with a well or group of wells of the plate and the lightdetector begins to acquire an image and the current/voltage sourcewithin the apparatus generates a waveform that is applied to the plate.The waveform may be adjusted by the apparatus depending upon the type ofdetection module installed in the assay system. After completion of thewaveform and image, the data are transferred from the light detector andcontrol board to a computer where they are processed. One or more assayprocessing steps may be modified or varied depending on the detectionmodule installed in the assay system.

The detection module comprises an identifier and the assay system,apparatus, or a component thereof comprises an identifier controllerthat interacts with the identifier. As described hereinbelow, theidentifier includes information concerning the detection module, whichmay include but is not limited to, the identity of the detection moduleand it's component parts (e.g., by serial and/or lot number), theconfiguration of the detection module, how the detection module ismanufactured and handled prior to use and/or how the detection module isused in an apparatus. In one embodiment, the invention provides anapparatus configured to use a detection module in the conduct of anassay, wherein the detection module includes a detection moduleidentifier as described herein and the apparatus includes (a) a storagemedium comprising detection module data; and (b) a reader adapted toread information from the detection module identifier andrelate/cross-check detection module information stored to the detectionmodule identifier to that stored to the apparatus' storage medium. Thedetection module data stored to the storage medium includes detectionmodule identification and/or configuration information and one or moresteps of an assay protocol that may be applied by the apparatus in theconduct of an assay using various detection modules. Therefore, thedetection module identifier includes information that may be used toidentify a specific detection module, e.g., a serial number for anindividual detection module, and the corresponding detection module datastored to the apparatus includes information that is used to identify adetection module associated with the apparatus as well as informationthat is used by the apparatus once the detection module is identified tocarry out an assay protocol using that detection module. Alternatively,the detection module information stored to the identifier includes allthe information required to identify and appropriately configure/adjustthe apparatus for use of the detection module.

In one embodiment, one or more steps of an assay protocol may betailored to an individual detection module. One or more steps of aprotocol may differ from individual detection module to detection moduleand the detection module data and/or information stored to the apparatusand detection module identifier, respectively, includes instructions totailor those steps of the assay protocol for a given detection module.This type of detection module data and/or information may be used by theassay system and/or apparatus to adjust one or more operations performedby the assay system and/or apparatus before, during and/or after theconduct of an assay by the assay system and/or apparatus. Moreover, thistype of detection module data and/or information may optionally beadjusted by the system and/or apparatus user at the user's discretion.

In another embodiment, the detection module data and/or informationfurther includes one or more analytical tools that may be applied by theassay system and/or apparatus to analyze data generated during and/orafter the conduct of an assay. In this embodiment, the detection moduledata and/or information is used by the assay system and/or apparatus toadjust the analytical processing tools applied by the system and/orapparatus software in the conduct of an assay or after the assay iscompleted and the results are generated and/or displayed. Suchanalytical processing tools include but are not limited to assaythresholds and/or calibration curves that may be applied to one or moresteps of an assay protocol that may also be altered based on detectionmodule differences.

In a preferred embodiment, the detection module data and/or informationmay be used by the assay system and/or apparatus to adjust the operationof a component of the apparatus selected from the group consisting ofone or more sensors; mechanisms to align and orient the detection modulewith said one or more sensors and/or with electrical, mechanical orfluidic interfaces in said apparatus, and/or to align and orient one ormore assay consumables used by the apparatus in relation to thedetection module and/or a component thereof. In a particularly preferredembodiment, the system and/or apparatus uses a multi-well plate or assaycartridge and the light detector within the detection module should beproperly aligned and oriented with respect to a well, grouping of wells,or segment of the plate or cartridge for effective light detectionduring the conduct of an assay. Appropriate alignment and orientation ofthe light detector within the detection module may be adjusted bydetection module information stored to the detection module identifierthat is read and processed by the apparatus when the detection module ismated to the chassis of the apparatus. Alternatively, if the detectionmodule is adapted to use a specific type of multi-well assay plate, itis programmed with that identification information which is used by thedetection module to adjust the imaging system for analysis and imageprocessing of that specific type of multi-well assay plate.Additionally, if a high resolution detection module is placed in anapparatus, the high resolution detection module is programmed withinformation to identify the specific model of detection module and theapparatus uses this identification information to adjust one or morecalibration and/or assay parameters to adapt the apparatus for use witha high-resolution detection module.

In one embodiment, the detection module identifier comprises memory forstoring information related to the module and its use. In oneembodiment, the memory is non-volatile memory. Non-volatile memory iscomputer memory that can retain the stored information without power.Examples of non-volatile memory which may be used in the consumableidentifier include, but are not limited to, electronic non-volatilememory (e.g., read-only memory and flash memory), magnetic memory (e.g.,hard disks, floppy disk drives, and magnetic tape), optical memory(optical disc drives) and hybrids of these approaches (e.g.,magneto-optical memory).

In one embodiment, the detection module identifier comprises EPROM(erasable programmable read-only memory), a type of programmableread-only memory that can be erased by exposing it to ultraviolet light.Once erased, it can be reprogrammed with new or modified data. Inanother embodiment, the detection module identifier comprises EEPROM(electronically erasable programmable read-only memory) a class ofnon-volatile electronic memory that can be electrically erased andreprogrammed without exposure to UV light. An EEPROM can be written toor programmed more than once and can be selectively programmed (the usercan alter the value of certain cells without erasing the programming ofthe other cells). Therefore, sections of data can be erased and replacedwithout needing to alter or reinstall the rest of the chip'sprogramming.

In another embodiment, the detection module identifier comprises flashmemory, a specific type of EEPROM that is erased and programmed in largeblocks. Although flash memory is technically a type of EEPROM, the term“EEPROM” is generally used to refer specifically to non-flash EEPROMwhich is erasable in small blocks, typically bytes. Because erase cyclesare slow, the large block sizes used in flash memory erasing give it asignificant speed advantage over conventional EEPROM when writing largeamounts of data.

In another embodiment, the detection module identifier comprises a smartcard, chip card, or integrated circuit card (ICC) (referred tocollectively as “ICCs”). These are small cards with embedded integratedcircuits which can process and store data. There are two broadcategories of ICCs; i) “memory cards” that contain non-volatile memorystorage components and, optionally, some specific security logic but donot contain microprocessors and i) “microprocessor cards” that combinenon-volatile memory components with microprocessor components and enablethe processing of information being read into or out of the ICC. The ICCelectronic components are supported on a card that is, typically, madeof plastic such as PVC or ABS. The card may include an embedded hologramto avoid counterfeiting. Contact ICCs have conductive contact pads. Wheninserted into a reader, the contact pads on the ICC make contact withelectrical connectors in the reader to allow for transfer of informationbetween the reader and the ICC, for example, allowing the reader toread, erase or write information on the ICC.

Another method of transferring information is via an RFID, i.e., radiofrequency identification, which is similar in theory to bar codeidentification. With RFID, the electromagnetic or electrostatic couplingin the RF portion of the electromagnetic spectrum is used to transmitsignals. An RFID system consists of an antenna and a transceiver, whichread the radio frequency and transfers the information to a processingdevice, and a transponder, or tag, which is an integrated circuitcontaining the RF circuitry and information to be transmitted.

Identification can also be accomplished by reading a bar code. One ofthe key differences between RFID and bar code technology is that RFIDeliminates the need for line-of-sight reading that bar coding dependson. Also, RFID scanning can be done at greater distances than bar codescanning. High frequency RFID systems (850 MHz to 950 MHz and 2.4 GHz to2.5 GHz) offer transmission ranges of more than 90 feet, althoughwavelengths in the 2.4 GHz range are absorbed by water (the human body)and therefore has limitations.

In one embodiment, the non-volatile memory used in the present inventionis selected from the group consisting of an EEPROM, flash memory, ICCand combinations thereof. In one embodiment, the non-volatile memory isan EEPROM. In an alternate embodiment, the non-volatile memory is anRFID.

The apparatus of the present invention includes an identifier controllerthat controls the operation of the non-volatile memory and othercomponents of the apparatus. The identifier controller optionallyincludes a micro-controller to interface with the non-volatile memoryover a communication interface, which may incorporate conventionalinterface architectures and protocols such as I2C, a two line serial busprotocol. The microcontroller addresses the non-volatile memory andperforms write, read and erase operations on the memory.

While certain embodiments of the detection module and apparatusdescribed herein call for the use of multi-well assay plates, this ismerely for illustrative purposes and the detection module of the presentinvention may be integrated into any number of different assay systemsand/or apparatuses to suit a given user's needs. For example, adetection module can be configured for use in an apparatus designed toanalyze a sample delivered via any of a variety of sample deliverymethods, e.g., multi-well assay plates, sample tubes, cartridges, and/orflow cells, and conduct a biological assay in any of a variety of assayformats. In this regard, reference is made to U.S. Pat. Nos. 6,066,448;6,090,545; 6,140,045; 6,207,369; 7,824,925; 7,842,246; 6,977,722;7,497,997; 7,807,448; and U.S. patent application Ser. Nos. 11/300,808;11/642,968; 12/422,08; 12/796,921; and 12/844,440, the disclosures ofwhich are incorporated herein by reference in their entireties.Moreover, the detection modules, apparatus, and assay systems describedherein may be used with a variety of assay detection techniquesincluding, but not limited to, techniques measuring one or moredetectable signals. Certain embodiments are suitable forelectrochemiluminescence measurements and, in particular, embodimentsthat are suitable for use with multi-well plates with integratedelectrodes (and assay methods using these plates) such as thosedescribed in U.S. Publication Nos. 2004/0022677 and 2005/0052646 of U.S.application Ser. Nos. 10/185,274 and 10/185,363, respectively, ofWohlstadter et al., and U.S. application Ser. No. 11/642,970 of Glezeret al. ECL-based multiplexed testing is described in U.S. PublicationNos. 2004/0022677 and 2004/0052646 of U.S. application Ser. Nos.10/185,274 and 10/185,363, respectively; U.S. Publication No.2003/0207290 of U.S. application Ser. No. 10/238,960; U.S. PublicationNo. 2003/0113713 of U.S. application Ser. No. 10/238,391; U.S.Publication No. 2004/0189311 of U.S. application Ser. No. 10/744,726;and U.S. Publication No. 2005/0142033 of U.S. application Ser. No.10/980,198.

In one embodiment the apparatus includes various components used in theconduct of an electrochemiluminescence (ECL) assay on a multi-well platehaving integrated electrodes. For example, the apparatus (or reader)includes a light-tight enclosure (LTE), a fluidic assembly (includingbut not limited to, e.g., pumps/valves, a pipettor subassembly, a probe,fluidic sensors, fluidic lines leading to and/or from a reagent/wastesubassembly and/or a wash subassembly, etc.) an imaging assembly, and anassembly capable of supporting and translating a plate to one or morecomponents of the apparatus. The apparatus may further comprise varioustranslation mechanisms to move additional components of the apparatus.Furthermore, the apparatus may comprise computers or other electronicsystems for controlling the operation of the apparatus including, e.g.,operating motorized mechanical systems and triggering and/or analyzingluminescence signals. Still further, the apparatus may include thenecessary electronic components and/or active mechanical components forcarrying out an assay measurement, e.g., one or more sources ofelectrical energy, ammeters, potentiometers, light detectors,temperature monitors or controllers, pumps, valves, a microprocessor forcontrolling the mechanical and/or electronic subsystems, analyzing theacquired data and/or providing a graphical user interface (GUI). Thesecomponents may be conventional components such as components known inthe art.

In one specific embodiment, the apparatus includes a fluidics subsystemwhich may comprise one or more of the following components: a pump/valvesyringe, a probe, a sample station, tubing, a reagent subassembly,interface fittings for sample and/or waste, and combinations thereof.The apparatus may further include electronics selected from the groupconsisting of: power distribution printed circuit board (PCB), PCBsdesigned to control movement of probes in the X, Y or Z-axes, a contactboard PCB, a motor driver PCB; a bar code reader, an elevator sensorPCB, a LTE PCB, cables, and combinations thereof. Still further, theapparatus may include a motion control subsystem including a componentselected from the group consisting of: a LTE door, a plate loadmechanism, a plate piercing mechanism assembly, a contact mechanism, aplate carriage, plate and probe motion control subassemblies (optionallyindependently controlling plate and/or probe motion in the X, Y orZ-axis), and combinations thereof. Moreover, the apparatus may include astructural component selected from the group consisting of: a LTEhousing, a probe axis assembly, component support brackets, mountingframes and/or reinforcing members, and combinations thereof.

Components, sub-systems and sub-assemblies suitable for use in theapparatus are disclosed in U.S. Application Nos. 61/123,975; 60/752,475;60/726,023; 60/752,513; Ser. Nos. 11/642,970; 11/642,968 (published asUS 2007/0231217); and Ser. No. 12/422,081, the disclosures of which areincorporated herein by reference. In particular, reference is made toFIGS. 1 to 3 and the accompanying description, e.g., on page 5, of US2007/0231217, and these specific disclosures are incorporated herein byreference in their entireties.

The external input/output connectors are selected from the groupconsisting of Ethernet, keyboard, mouse, video, USB, RS-232, PCMCIAcards, PCI boards, power, networking devices, modems, user inputdevices, display, data storage devices, and combinations thereof.

A computer within or connected to the apparatus participates in theoperation, control, management of data and monitoring of the apparatus,the detection module and/or other peripheral devices. The softwarerequired to operate the apparatus and/or the detection module, manageand analyze data collected on the apparatus and/or detection module maybe provided with the apparatus and/or detection module or as a separatecomponent of the system.

The detection module, apparatus, and assay system may be specificallydesigned to reliably operate in a broad range of environmentalconditions, including but not limited to, low pressure for altitudetesting, exposure to high and low temperatures plus temperature shock(both operating and in storage), rain (including wind-blown and freezingrain), humidity, fungus, salt, fog for rust testing, sand and dustexposure, explosive atmosphere, leakage, acceleration, shock andtransport shock (i.e., triangle/sine/square wave shocks), gunfirevibration, and random vibration. In a specific embodiment, the detectionmodule, apparatus, and/or assay system is designed to comply withMIL-STD-810G, which specifically addresses shock and vibration stress,and MIL-STD-461, which addresses the requirements for the control ofelectromagnetic interference characteristics of subsystems andequipment.

Accordingly, the detection module and/or system housing may befabricated, in whole or in part, from a substance selected from thegroup consisting of metal (steel and/or aluminum), plastic, magnesiumalloy, and combinations thereof. In one embodiment, if the substance isnon-metal it may be spray coated with a metal paint or conductivecoating, e.g., nickel. In addition, the detection module, apparatus, andassay system may include one or more shock-mounted components and/orsealed I/O ports. The detection module and/or system housing may beelectrically grounded and the components of the detection module,apparatus, and assay system each make electrical contact with oneanother and are grounded. The detection module and/or system housing mayinclude one or more vents and those vents are optionally sized for EMIcontrol, e.g., vents should comprise a round hole pattern and the holesin the pattern should be as small as practical, e.g., less than about0.2 inches in diameter, and in one embodiment, approximately 0.125inches in diameter. In a preferred embodiment, the vent holes are notslots. Still further, areas within the detection module, apparatus, andassay system for placement of connectors should be sized appropriatelyfor the connector and EMI gaskets may be used to seal connectors. EMIshields may be placed directed onto printed circuit boards to enhanceEMI shielding and ferrites (i.e., magnets that wrap around cables) maybe used on cables external to the detection module, apparatus, and assaysystem to filter any EMI picket up by the cables.

Structural components of the detection module, apparatus, and assaysystem may be made from aluminum, titanium, or engineering plastics,such as glass-filled polymers, to maximize strength of the structurewhile minimizing mass. Printed circuit boards may be made fromfiberglass stock of sufficient thickness to increase stiffness of theboard (preferably greater than 0.062 inches, and more preferably betweenabout 0.09 to 0.125 inches) and have additional mounting locations tominimize the effects of shock and/or vibration. Vibration isolators maybe used at mounting locations. Moreover, vibration control may beachieved using passive technologies, e.g., passive damping usingviscoelastic materials, viscous dampers (dashpots), tuned-mass dampers,dynamic absorbers, shunted piezoceramics dampers, and magnetic dampers.Printed circuit boards may have conformal coatings (i.e., a polymerlayer applied to printed circuit board after manufacturing) to increasetheir resistance to high ambient humidity, salt, fog, and otherenvironmental conditions. In addition, printed circuit boards maycomprise relatively thick copper traces on the board, e.g., greater than8 mils, and/or the boards do not include large cantilevered componentsto reduce the impact of shock and vibration within the detection module.The housing of the detection module, apparatus, and assay system mayinclude seals for connectors or other openings. Cables may bestrain-relieved and optionally include locking connectors on each end.In addition, fasteners may have locking features (nylon patch, loctite,lock washers, SEMS, etc.) and the lens aperture of the detector modulemay include a lens cover.

In one embodiment, the detection module, apparatus, and assay system mayinclude heaters and/or coolers (e.g., a thermoelectric heater/cooler,liquid cooled pipes) and/or a desiccant chamber to maintain thedetection module, apparatus, and assay system under controlledtemperature and/or humidity. In addition, the detection module,apparatus, and assay system may include a ventilation mechanism, e.g., afan, to control temperature within the detection module, apparatus, andassay system.

* * *

Patents, patent applications, publications, and test methods cited inthis disclosure are incorporated herein by reference in their entirety.

The present invention is not to be limited in scope by the specificembodiments described herein. Indeed, various modifications of theinvention in addition to those described herein will become apparent tothose skilled in the art from the foregoing description and accompanyingdrawings. Such modifications are intended to fall within the scope ofthe claims.

A claim which recites “comprising” allows the inclusion of otherelements to be within the scope of the claim; the invention is alsodescribed by such claims reciting the transitional phrases “consistingessentially of” (i.e., allowing the inclusion of other elements to bewithin the scope of the claim if they do not materially affect operationof the invention) or “consisting of” (i.e., allowing only the elementslisted in the claim other than impurities or inconsequential activitieswhich are ordinarily associated with the invention) instead of the“comprising” term. Any of these three transitions can be used to claimthe invention.

We claim:
 1. A detection module configured for placement and functionalengagement with an apparatus for conducting luminescence assays inmulti-well plates, said apparatus comprising one or more detectionmodule engagement elements, said detection module is a replaceable unitdisposed within a detection module housing, and wherein the followingcomponents are disposed within said housing: (a) a light detector; and(b) a control board comprising (i) a microcontroller, (ii) motioncontrol and communications electronics, (iii) an external input/outputconnector, and (iv) an internal input/output connector; wherein saidhousing comprises one or more apparatus engagement elements configuredto align and engage with said one or more detection module engagementelements.
 2. A system comprising (a) an apparatus for conductingluminescence assays in multi-well plates, said apparatus comprising alight-tight enclosure (LTE), a fluidic assembly, an imaging assembly, aplate assembly capable of supporting and translating a plate to one ormore components of said apparatus; and one or more detection moduleengagement elements; (b) a detection module configured for placement andfunctional engagement with said apparatus, said detection module is areplaceable unit disposed within a detection module housing, and whereinthe following components are disposed within said housing: (x) a lightdetector and (y) a control board comprising (i) a microcontroller, (ii)motion control and communications electronics, (iii) an externalinput/output connector, and (iv) an internal input/output connector;wherein said housing comprises one or more apparatus engagement elementsconfigured to align and engage with said one or more detection moduleengagement elements.
 3. A method of conducting a luminescence assay inan assay system of claim 2 using a multi-well assay plate comprising:(a) inserting said detection module into said apparatus, (b) engagingsaid apparatus and detection module engagement elements, (c) insertingsaid multi-well assay plate within a light-tight enclosure of saidapparatus, (d) generating a current/voltage waveform in said detectionmodule, (e) providing electrical energy to a well of said assay plate insaid light-tight enclosure, and (f) measuring luminescence from saidassay plate in said detection module.
 4. An apparatus for conductingluminescence assays in multi-well plates, said apparatus comprising alight-tight enclosure (LTE), a fluidic assembly, an imaging assembly, aplate assembly capable of supporting and translating a plate to one ormore components of said apparatus; and one or more detection moduleengagement elements configured to align and engage with a detectionmodule of claim 1 via said one or more apparatus engagement elements.